Studies on the active principles of the Olea europea have been conducted for decades, and their properties were recently confirmed in experimental and clinical studies.1 
It was reported that oleuropein, the main component detectable in the leaves, is the compound responsible for hypotension, coronary dilating and antiarrhythmic action. In one study2 the antihypertensive, diuretic, antiaretheriosclerotic, antioxidant and hypoglicemic effect of triterpenoids isolated from Olea europea leaves were confirmed in a salt-sensitive genetically hypertensive rats model. Olive leaf extract also contains other synergistic phytochemicals including rutin and hesperidin. They are vital in their ability to increase the strength of the capillaries (blood vessels) and to regulate their permeability.
As far as olive oil is concerned, several studies have shown the important role of phenolic compounds contained therein. The main components, tyrosol, verbascoside and hydroxytyrosol, are potent inhibitors of LDL oxidation in vivo,3-4 which is linked to the formation of atherosclerosis plaques that are postulated to contribute to the development of coronary heart disease. Hydroxytyrosol has been reported to reduce, alone, the risk of coronary heart diseases and atherosclerosis5-6, being in vitro a potent and dose-dependent inhibitor of copper sulfate-induced oxidation of LDL. These results were also obtained in the animal model.7 Verbascoside has been proved to possess potent scavenging actions on superoxide anions and hydroxyl radicals,8-9 and also to act an antioxidant to inhibit the peroxidation of mouse liver microsome, rat liver mitochondria, the emolysis of erythrocytes induced by radicals; its antioxidant potential has been revealed in many other experimental models.
Recent studies have demonstrated that virgin olive oil phenolic components, such as hydroxytyrosol and its secoiridoid derivatives and metabolites—namely compounds with an ortho-diphenolic structure—exert strong antioxidant, as well as other biologically relevant effects.10-11 Although most of these results have been obtained in in vitro systems,12-13 evidence of the biological activities of olive oil phenolics in vivo is also accumulating.14-15 Hydroxytyrosol (HT) is apparently the most active of olive phenols, it has been shown to be dose-dependently absorbed in humans, though to different degrees according to its formulation. As an example, its incorporation into a yoghurt decreases its bioavailability when compared to that after administration as a natural component of extra virgin olive oil.16 
Therefore, it is highly desirable to find olive fruits extracts derivatives having improved bio availability.
Complex compounds of vegetable extracts or of purified components thereof with natural, synthetic or semi-synthetic phospholipids, have been disclosed, e.g., in EP 209 038, EP 275 005, EP 283 713, EP 1 035 859 and EP 1 140 115. The mentioned complexes improve the plasma bioavailability of the extract or purified component, due to their lipophilicity. EP 275 005 states that the formation of the complexes is carried out in an aprotic solvent. EP 1 140 115 generically mentions ethanol among the various solvents that can be used of the preparation of mentioned complexes, but does not provide preparation examples which make use of ethanol as the solvent. Furthermore, the complexes disclosed are phospholipid complexes of proanthocyanidin A2, which are quite different in the chemical structure with respect to the phospholipids complexes of olive fruits extracts of the present invention.